View Full Version : GH4 4K Slow Motion Via FCPX?


Ronald Jackson
December 14th, 2014, 03:41 AM
Nice slo mo effects with a GH4 via the "variable frame rate setting" but 1080p.

How can I achieve a slo-mo effect but 4K (or UHD) resolution via FCPX?

I wonder if anyone's tried yet and if there are samples to show.


Ron

Dave Partington
December 14th, 2014, 09:20 AM
Select the clip in the timeline then change the speed to 50%, 25% or other custom setting. Make sure you then go to the Video Quality menu and change to Optical Flow since the normal version only uses frame blending.

Depending on the scene I've had luck slowing things down to anywhere between 10% and 50%. Occasionally if the scene has really clear lines that don't overlap then 5% has been possible too.

Make sure you give it time to analyse the clip (could take several minutes for longer clips) otherwise you're only going to see the frame blending version which isn't great.

Ronald Jackson
December 17th, 2014, 06:30 AM
Thanks Dave, tried that. Not too good at 25%, a flock of flying Lapwings but not so bad at 50%.

One thing though with these initial forays into 4K with FCPX is the enormous file sizes. A 200MB clip becomes 8GB when slowed to 25%. The same clip at normal speed becomes 2GB.

I'm "share/saving" at default Master Quality. Presumably there is something below this which still preserves the 4K resolution.

I have "Compressor" but have never used it. I don't even understand what it's supposed to do. Apple instructions/explanations a little opaque, they seem to assume you know everything so no need to explain.

Ron

Dave Partington
December 17th, 2014, 11:12 AM
A 200MB clip becomes 8GB when slowed to 25%. The same clip at normal speed becomes 2GB.

Given that the clip is now four times longer (25% = 4 frames for every original one) then it\s no surprise that the video is 4 times bigger if you're saving out to ProRes.

OTOH, if you were slowing it down to fit in to (say) a 5 second clip then of course the size would be the same, based on time.

You can save 4K in H264 if you want, you don't have to use ProRes, but much would depend on what you are using the file for from here on.

Ronald Jackson
December 18th, 2014, 03:52 AM
Thanks again Dave. I am saving so as to be able to play a 4K (UHD in fact) movie on my 4K monitor via output from my iMac (which "outs" 4K) and eventually an updated MBP, my current one does not "out" 4K.

When and if there are 4K BD burners and players that might be the way to go.


How does one share as H264 in FCPX though?

Ron

Ronald Jackson
December 18th, 2014, 06:45 AM
Okay Dave, found it! File size similar to that of the original import,


Thanks,


Ron

Dave Partington
December 18th, 2014, 11:10 AM
Glad to hear you found it. Have fun :)